Can I plug in my Boss gt8 guitar effects into the presonus audiobox usb front instrument panel? Thanks

You CAN make this connection but it is not recommended. The reason is that the AudioBox USB already has preamps in both inputs. By connecting powered hardware, such as your effects processor, you can overdrive and potentially damage your AudioBox USB's preamps. This is covered in the AudioBox manual as well. Here's a screenshot of the relevant info from the manual: http://imgur.com/JdAMTbB